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Show 1884.] 'LIGHTNING' A N D 'PORCUPINE' EXPEDITIONS. 115 oval : outer lip thin, smooth within: inner lip somewhat reflected and thickened on the lower part of the pillar, which is imperforate. L. 0075, B. 0-045. ' Porcupine ' Exp. 1870 : Atl. St. Tangier B. Two specimens. Differs from R. punctura in being more slender or narrower and of an oblong shape ; and the sculpture is not reticulated. 12. RISSOA SUBSOLUTA, Aradas. (Plate IX. fig. 3.) R. subsoluta, Ax. Mem. di Malac. Sic. iii. (1847), p. 21. ' Porcupine ' Exp. 1870 : Atl. St. 1, 3, 9, 13, 14, 16, 24, 26. Distribution. Bay of Biscay ('Travailleur' Exp. 1880)! ; Mediterranean (Nares, Spratt, Monterosato) ; 108-310 fms. Fossil. Pliocene : Messina (Seguenza) ! In some specimens (as described by Aradas) the longitudinal striae partially disappear, or are entirely wanting, on the last and penultimate whorls. The sculpture of this pretty little shell is much finer than that of the next species (B. testa), and the spire is more bluntly pointed. I described it in my paper on Mediterranean Mollusca (Ann. & Mag. N. H. 1870) as the variety obtusa of that species under the name of R. abyssicola. At one time I considered the species named and described by Aradas the same as that which I now propose to call deliciosa, and which will he described and figured in this paper ; but I have since been enabled to rectify the mistake by the examination of a typical specimen of R. subsoluta, which I received from the late Professor of Catania. The present species is R. elegan-tissima of Seguenza. 13. RISSOA TESTAE, Aradas & Maggiore. (Plate IX. fig. 4.) R. testa, Ar. & Magg. Cat. rag. Catania, 1844, p. 207. ' Porcupine ' Exp. 1869 : St. 2, 3,10, 16. 1870 : Atl. 3a, Vigo B., Setubal B., 22, 24, off C. Sagres, 26-34, 36 ; Med. 40, 41, 45, Cartagena B., 50, Benzert Road, Adventure Bank, off Rinaldo's Chair. In most of the first-named Stations the variety abyssicola is the prevalent form. That variety is more oval, and has a rather more oblique spire and finer sculpture than the typical form; it is described and figured in the ' British Mollusca,' vol. iii. p. 86, pi. lviii. f. 1, 2, and (animal) pi. JJ. f. 3, and in " British Con-chology,' vol. iv. p. 19, and v. p. 207, ph lxvi. f. 9. Distribution. Typical form : Atlantic coasts of France and Spain to the Mediterranean and Adriatic ; 11-640 fms. Var. abyssicola : Arctic, Norway to Mizen Head, Co. Cork ; 30-300 fms. Fossil. Typ. Pliocene: Italy. Var. abyssicola. Post-tertiary: Christiania district (Crosskey and Robertson). In the above-cited paper on Mediterranean Mollusca I named the present species the variety conformis of R. abyssicola, not being then aware of the publication by Aradas and Maggiore. I afterwards received from the lamented Professor Aradas typical specimens of B. testa which not only confirmed my opinion that it was the |